简支桁架组合楼盖的优化设计研究

发布时间：2018-04-18 02:21

本文选题：简支桁架组合楼盖 + 有限元分析　；参考：《清华大学》2015年硕士论文

【摘要】：近年来,我国大型及特大型公共建筑和高层建筑得到迅猛发展,对大跨重载结构产生巨大需求。与此同时,资源能源浪费、环境污染等问题已成为目前结构工程领域面临的重要挑战。钢桁架-混凝土组合梁(后简称:桁架组合梁)通过栓钉连接件将钢桁架与混凝土板组合在一起协同工作,在大跨重载条件下具有优越的受力性能和经济优势,同时易于实现绿色施工。本文对简支桁架组合梁以及简支桁架组合楼盖的受力性能、设计方法、技术经济指标、设计优化等问题开展研究,完成的主要工作包括:1.在通用有限元程序ABAQUS的平台上,采用壳-实体混合有限元模型对简支桁架组合梁的受力性能开展研究,并通过实验结果加以验证。基于该有限元模型,通过参数分析对简支桁架组合梁基于刚度等效的有效翼缘宽度进行分析,提出基于刚度等效的有效翼缘宽度计算公式,与规范相比能够更好地预测简支桁架组合梁的结构刚度和变形。在现行规范建议的实腹式组合梁设计方法的基础上,给出了简支桁架组合梁的承载力极限状态设计方法几点建议;2.基于塑性极限承载力设计方法,在保证相同极限弯矩的条件下,针对用钢量指标,对简支桁架组合梁和简支工字钢组合梁的杆件截面参数进行优化分析,可知高跨比、桁架组合梁弦杆面积比、工字钢组合梁翼缘面积比对组合梁用钢量指标的影响最大。此外,基于对桁架组合梁以及工字钢组合梁同参数条件下的用钢量对比分析得到了相关优化设计建议;3.采用梁-壳混合有限元模型,在满足塑性承载力设计要求的条件下,通过控制楼盖应力的方式对简支桁架组合楼盖和简支工字钢组合楼盖的用钢量进行楼盖布置的参数分析、以及同参数条件下简支桁架组合楼盖和简支工字钢组合楼盖用钢量的对比分析,最后给出了工程设计时考虑用钢量指标的结构选型建议;4.结合某实际工程大跨重载组合楼盖的优化设计,对本文提出的考虑用钢量指标的结构选型建议进行了验证。设计结果表明:简支桁架组合梁及桁架组合楼盖在受力性能、楼盖舒适度、结构高度、用钢量、自重等方面综合指标优越,具有广阔的应用前景。
[Abstract]:In recent years, large and super large public buildings and high-rise buildings have been developed rapidly in our country, and there is a huge demand for large span and heavy load structures.At the same time, the waste of resources and energy, environmental pollution and other problems have become an important challenge in the field of structural engineering.Steel truss-concrete composite beams (hereinafter referred to as truss composite beams) work together with steel trusses and concrete slabs through bolt connectors, which have superior mechanical performance and economic advantages under the condition of long span and heavy load.At the same time, it is easy to realize green construction.In this paper, the mechanical behavior, design method, technical and economic index, design optimization of simply supported truss composite beam and composite floor of simply supported truss are studied. The main work accomplished includes: 1.On the platform of the universal finite element program ABAQUS, the mechanical behavior of simply supported truss composite beams is studied by using the hybrid finite element model of shell and solid, and the experimental results are verified.Based on the finite element model, the effective flange width based on stiffness equivalence of simply supported truss composite beam is analyzed by parameter analysis, and a formula for calculating effective flange width based on stiffness equivalence is proposed.Compared with the code, the stiffness and deformation of simply supported truss composite beams can be predicted better.On the basis of the design method of solid web composite beam suggested by the current code, several suggestions on the design method of bearing capacity limit state of simply supported truss composite beam are given in this paper.Based on the design method of plastic ultimate bearing capacity and under the condition of ensuring the same ultimate bending moment, the section parameters of simply supported truss composite beam and simply supported I-steel composite beam are optimized and analyzed under the condition of the same ultimate bending moment, and the ratio of height to span is known.The chord area ratio of truss composite beam and the flange area ratio of I-beam composite beam have the greatest influence on the steel quantity index of composite beam.In addition, based on the comparison and analysis of the amount of steel used in truss composite beams and I-beam composite beams with the same parameters, the relevant optimal design suggestions are obtained.In this paper, the beam-shell hybrid finite element model is used to analyze the parameters of floor layout of simply supported truss composite floor and simply supported I-steel composite floor by controlling the stress of the floor under the condition of satisfying the design requirements of plastic bearing capacity.In addition, the comparison and analysis of the steel consumption between the simple truss composite floor and the simple supported I-steel composite floor under the same parameters are given. Finally, the suggestion of structural type selection considering the steel quantity index in the engineering design is given.Combined with the optimization design of the large-span and heavy-load composite floor of a practical project, this paper verifies the suggestion of structural selection considering the steel quantity index in this paper.The design results show that the composite beam with simply supported truss and the composite floor of truss are superior in the aspects of mechanical performance, floor comfort, structural height, steel quantity, weight of body, and so on, and have a broad application prospect.
【学位授予单位】：清华大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TU398.9

【相似文献】